Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system

A fiber grating array and weak fiber grating technology, applied in the direction of measuring ultrasonic/sonic/infrasonic waves, measuring devices, instruments, etc., can solve the problems of low detection range and sensitivity, and achieve the effect of improving signal-to-noise ratio and sensitivity

Inactive Publication Date: 2015-12-23
UNIV OF ELECTRONIC SCI & TECH OF CHINA
View PDF3 Cites 33 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In the ordinary Φ-OTDR system, the detection range and sensitivity are relatively low, which is also a key problem that needs to be solved urgently

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system
  • Ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system
  • Ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0039] An optical fiber vibration sensing system combining an ultra-weak fiber grating array and a Φ-OTDR, in which an ultra-weak fiber grating array is connected to the sensing fiber part of the optical fiber vibration sensing system. The spacing of the ultra-weak fiber grating array is the same as the spatial resolution of the system or an integer multiple of the spatial resolution. The signal returned in the sensing fiber is the superposition of the reflection signal of the ultra-weak fiber grating and the back Rayleigh scattering signal.

Embodiment 2

[0041] An optical fiber vibration sensing system combining an ultra-weak fiber grating array and a Φ-OTDR, in which an ultra-weak fiber grating array is connected to the sensing fiber part of the optical fiber vibration sensing system. Each ultra-weak fiber grating should be arranged at equal intervals in the sensing fiber. The spacing of the ultra-weak fiber grating array is the same as the spatial resolution of the system or an integer multiple of the spatial resolution. The signal returned in the sensing fiber is the superposition of the reflection signal of the ultra-weak fiber grating and the back Rayleigh scattering signal.

Embodiment 3

[0043] An optical fiber vibration sensing system combining ultra-weak fiber grating array and Φ-OTDR, the sensing fiber adopts ultra-weak fiber grating array. The spacing of the ultra-weak fiber grating array is the same as the spatial resolution of the system or an integer multiple of the spatial resolution. The signal returned in the sensing fiber is the superposition of the reflection signal of the ultra-weak fiber grating and the back Rayleigh scattering signal.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The present invention discloses an ultraweak fiber bragg grating array and Phi-OTDR combined optical fiber vibration sensing system. According to the system, the ultraweak fiber bragg grating arrays are accessed in a sensing optical fiber with the same spacing, and the spacing selection must be same with the spatial resolution of a Phi-OTDR optical fiber sensing system or must be integer multiples of the spatial resolution. By utilizing the reflection characteristics of the ultraweak fiber bragg gratings, the optical power of the detected backward rayleigh scattered light is improved, thereby improving the signal to noise ratio and the sensitivity of the Phi-OTDR optical fiber vibration sensing system.

Description

technical field [0001] The invention relates to the technical field of optical fiber vibration sensing system based on Φ-OTDR, mainly improving the structure of sensing optical fiber, and specifically relates to an optical fiber vibration sensing system combining an ultra-weak fiber grating array and Φ-OTDR. Background technique [0002] In the Φ-OTDR optical fiber vibration sensing system, the continuous light wave emitted by the narrow linewidth laser is injected into the sensing fiber through the circulator after pulse modulation and optical amplification. The light injected into the fiber in Φ-OTDR is strongly coherent, so the output of the system is the result of the interference of backscattered Rayleigh light within the pulse width range. Assuming that the sensing fiber is in an ideal state, the back Rayleigh scattering waveform returned through the sensing fiber should be constant, if a perturbation is added to a certain point in the sensing fiber, then the sensing f...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G01H9/00
Inventor 岳慧敏熊竹魏豪李剑峰张博
Owner UNIV OF ELECTRONIC SCI & TECH OF CHINA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products